The IPv6 Traffic Class to use by default when sending IPv6 Neighbor Discovery (Router Solicitation, Router Advertisement, Neighbor Solicitation, Neighbor Advertisement, Redirect) messages. These 8 bits can be interpreted as 6 high order bits holding the DSCP value and 2 low order bits representing ECN (which you probably want to leave cleared). 0 - (default)
Nb: per interface setting (where “interface” is the name of your network interface); “all” is a special interface: changes the settings for all interfaces.
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